Graeser M, Harbeck N, Gluz O, et al. - This study was intended to evaluate the value of breast ultrasound (US) conducted at week 3 and 6 and at the end (EOT) of neoadjuvant therapy (NAT) for prediction of pathologic complete response (pCR, ypT0/is ypN0) in patients with HR+/HER2+, HR-/HER2-or HR-/HER2+ early breast cancer enrolled in the WSG-ADAPT subtrials. Researchers conducted US at week 3 and 6 of NAT and at EOT in 401, 517, and 553 patients, respectively. Furthermore, tumors with complete or partial response by US (RECIST 1.1) were categorized as responders and those with stable or progressive disease as non-responders. The findings illustrate the use of week 3 and EOT US for prediction of pCR in response-guided NAT and in planning of breast-conserving surgery. It has been reported that change in tumor diameter in the US as a continuous variable could be a valuable alternative to categorical RECIST 1.1 criteria.